Objective To establish normal reference values of video head impulse test(vHIT)for civil avia-tion student pilots to provide a reference basis for the accurate assessment of the vestibular function of civil aviation student pilots.Methods Forty civil aviation student pilots in the theoretical training phase were randomly selected for vHIT.The average gain of the vestibulo-ocular reflex(VOR)and the asymmetry ratios of the semicircular ca-nals were compared.Results The VOR values for the right horizontal,anterior,and posterior semicircular canals were 1.05±0.07,0.92±0.13,0.81±0.09,respectively.For the left horizontal,anterior,and posterior semicir-cular canals,the values were 1.00±0.06,0.85±0.10,0.86±0.10,respectively.There was no compensatory sac-cade in any of the subjects.The asymmetry ratios of bilateral horizontal,left anterior-right posterior,and right an-terior-left posterior semicircular canals were 5.56％±3.64％,9.65％±4.74％,8.68％±7.07％,respectively.Conclusion This study establishes vHIT normal reference values for civil aviation student pilots,providing an ob-jective basis for their selection and vestibular function evaluation.

Objective:To investigate the diagnosis, treatment, prognosis and aeromedical assessment of nasopharyngeal non-Hodgkin lymphoma (NHL) in civil aviation pilots.Methods:The clinical data of a civil pilot with nasopharyngeal NHL was retrospectively analyzed while related literature was reviewed. The clinical characteristics, diagnosis, treatment, prognosis and identification of nasopharyngeal NHL were traced.Results:A civil pilot was diagnosed with nasopharyngeal NHL in January 2016 before being grounded by aviation physicians. After treatment with systematic chemoradiation and chemotherapy by the Department of Oncology, West China Hospital of Sichuan University, the patient′s results of blood routine tests, blood biochemistry, EB virus DNA detection, electrical audiometry, and sound immittance returned to normal as evidenced by multiple outpatient examinations between June 2016 and April 2017. No signs of malignant tumor were found by fiber nasopharyngoscopy, nasopharyngeal MRI or positron emission tomography/computed tomography. In June 2017, he applied for specially-permitted assessment for the first time, and the aeromedical assessment conclusion was waiver to flight, but his flight was limited to 60 h or less. The pilot was able to perform flight duties ever since. EB virus DNA detection, nasopharyngeal MRI, fiber nasopharyngoscopy and other related examinations were repeated in each physical examination, and the pilot was given specially-permitted eligibility for fight missions annually for 6 consecutive years, but the monthly flying hours was limited to 60 h or less. So far, the disease neither recurred nor progressed.Conclusions:Nasopharyngeal NHL is rare in civil aviation pilots, so missed diagnosis and misdiagnosis should be avoided. Patients with nasopharyngeal NHL who have recovered after treatment may apply for specially-permitted health assessment and resume their work after comprehensive assessment by related experts.

Objective To establish normal reference values of video head impulse test(vHIT)for civil avia-tion student pilots to provide a reference basis for the accurate assessment of the vestibular function of civil aviation student pilots.Methods Forty civil aviation student pilots in the theoretical training phase were randomly selected for vHIT.The average gain of the vestibulo-ocular reflex(VOR)and the asymmetry ratios of the semicircular ca-nals were compared.Results The VOR values for the right horizontal,anterior,and posterior semicircular canals were 1.05±0.07,0.92±0.13,0.81±0.09,respectively.For the left horizontal,anterior,and posterior semicir-cular canals,the values were 1.00±0.06,0.85±0.10,0.86±0.10,respectively.There was no compensatory sac-cade in any of the subjects.The asymmetry ratios of bilateral horizontal,left anterior-right posterior,and right an-terior-left posterior semicircular canals were 5.56％±3.64％,9.65％±4.74％,8.68％±7.07％,respectively.Conclusion This study establishes vHIT normal reference values for civil aviation student pilots,providing an ob-jective basis for their selection and vestibular function evaluation.

Objective:To investigate the diagnosis, treatment, prognosis and aeromedical assessment of nasopharyngeal non-Hodgkin lymphoma (NHL) in civil aviation pilots.Methods:The clinical data of a civil pilot with nasopharyngeal NHL was retrospectively analyzed while related literature was reviewed. The clinical characteristics, diagnosis, treatment, prognosis and identification of nasopharyngeal NHL were traced.Results:A civil pilot was diagnosed with nasopharyngeal NHL in January 2016 before being grounded by aviation physicians. After treatment with systematic chemoradiation and chemotherapy by the Department of Oncology, West China Hospital of Sichuan University, the patient′s results of blood routine tests, blood biochemistry, EB virus DNA detection, electrical audiometry, and sound immittance returned to normal as evidenced by multiple outpatient examinations between June 2016 and April 2017. No signs of malignant tumor were found by fiber nasopharyngoscopy, nasopharyngeal MRI or positron emission tomography/computed tomography. In June 2017, he applied for specially-permitted assessment for the first time, and the aeromedical assessment conclusion was waiver to flight, but his flight was limited to 60 h or less. The pilot was able to perform flight duties ever since. EB virus DNA detection, nasopharyngeal MRI, fiber nasopharyngoscopy and other related examinations were repeated in each physical examination, and the pilot was given specially-permitted eligibility for fight missions annually for 6 consecutive years, but the monthly flying hours was limited to 60 h or less. So far, the disease neither recurred nor progressed.Conclusions:Nasopharyngeal NHL is rare in civil aviation pilots, so missed diagnosis and misdiagnosis should be avoided. Patients with nasopharyngeal NHL who have recovered after treatment may apply for specially-permitted health assessment and resume their work after comprehensive assessment by related experts.

Objective:To evaluate the diagnosis of renal function impairment as the serum creatinine (Scr) level raised in pilots by determining the glomerular filtration rate (GFR) ( 99mTc-GFR) through diethylene triamine pentaacetic acid (DTPA) renal dynamic imaging standard method and to compare the accuracy of determining simply elevated Scr between the diagnosing of cystatin C (Cys C) and GFR evaluation for flying personnel. Methods:In this study, pilots and pilot cadets whose Scr level was diagnosed raised twice in the physical examinations at Civil Aviation Medical Center of Civil Aviation Administration of China during 2018-2019 were selected as subjects. The GFR was calculated by the evaluation equations of Cockcroft-Gault creatinine clearance (CG-CCr) and the modification of diet in renal disease (MDRD-GFR) upon the averaged Scr level. Blood Cys C and 99mTc-GFR were examined. According to the examination results, they were divided into 99mTc-GFR normal group ( 99mTc-GFR≥90 ml/min) and 99mTc-GFR reduced group ( 99mTc-GFR<90 ml/min). Results:A total of 95 cases were enrolled, all male with an average age of (35.27±10.32) years. There were 59 cases with renal function impairment, accounting for 62.1%. The correlation coefficients r of Scr, MDRD-GFR, Cys C, CG-CCr and total kidney 99mTc-GFR were 0.218, 0.535, 0.808, 0.857, respectively. There were statistically significant differences in MDRD-GFR, CG-CCr and Cys C between normal and reduced 99mTc-GFR groups ( P<0.01). Conclusion:The percentage of renal impairment in simple Scr raised pilots is 62.1%. Besides 99mTc-GFR, Cys C and CG-CCr have good diagnostic accuracy and can be used as a supplementary examination item for the patients with elevated Scr.

Objective:To evaluate the diagnosis of renal function impairment as the serum creatinine (Scr) level raised in pilots by determining the glomerular filtration rate (GFR) ( 99mTc-GFR) through diethylene triamine pentaacetic acid (DTPA) renal dynamic imaging standard method and to compare the accuracy of determining simply elevated Scr between the diagnosing of cystatin C (Cys C) and GFR evaluation for flying personnel. Methods:In this study, pilots and pilot cadets whose Scr level was diagnosed raised twice in the physical examinations at Civil Aviation Medical Center of Civil Aviation Administration of China during 2018-2019 were selected as subjects. The GFR was calculated by the evaluation equations of Cockcroft-Gault creatinine clearance (CG-CCr) and the modification of diet in renal disease (MDRD-GFR) upon the averaged Scr level. Blood Cys C and 99mTc-GFR were examined. According to the examination results, they were divided into 99mTc-GFR normal group ( 99mTc-GFR≥90 ml/min) and 99mTc-GFR reduced group ( 99mTc-GFR<90 ml/min). Results:A total of 95 cases were enrolled, all male with an average age of (35.27±10.32) years. There were 59 cases with renal function impairment, accounting for 62.1%. The correlation coefficients r of Scr, MDRD-GFR, Cys C, CG-CCr and total kidney 99mTc-GFR were 0.218, 0.535, 0.808, 0.857, respectively. There were statistically significant differences in MDRD-GFR, CG-CCr and Cys C between normal and reduced 99mTc-GFR groups ( P<0.01). Conclusion:The percentage of renal impairment in simple Scr raised pilots is 62.1%. Besides 99mTc-GFR, Cys C and CG-CCr have good diagnostic accuracy and can be used as a supplementary examination item for the patients with elevated Scr.

OBJECTIVE To investigate and analysis of hearing status and characteristics of China civil aviation air traffic controllers(ATC). METHODS With cluster random sampling, air conduction threshold data of 1498 ATC, who had finished the class Ⅲa medical assessment this year in a certain area were studied. The subjects were tested by pure tone audiometry, the prevalence rate of speech and high frequency hearing loss between gender groups were compared; After age correction, the threshold of different frequencies were compared between age groups. RESULTS The prevalence rate of hearing loss at speech frequency was 6.68％ in male and 1.97％ in female. The result of high frequency was 7.87％ and 1.23％ respectively. Both the threshold and prevalence rate of hearing loss of every frequency were higher in male(P<0.05); The threshold of 3000 Hz

Objective To study extended high frequency (EHF) audiometry for early detection of hearing loss in student pilots in civil aviation.Methods A total of 175 student pilots (all male,18~25 years old, mean 20.2±0.92 years) from a university flight academy were surveyed and underwent EHFA.All subjects had hearing thresholds ≤25 dB HL at conventional frequencies (0.25~8 kHz).The results were compared with the corresponding recommended standards in other countries.According to the use of personal listening devices, all the subjects were divided into the low risk group (non-use, 121 cases) and the high risk group (using>1 year, day>1 hour, 52 cases).The differences of hearing thresholds and detection rates at EHF between the two groups were compared.Results The hearing thresholds of 173 subjects (1 case of middle ear disease and 1 case with family history of hearing loss were excluded) at 9~20 kHz were slightly higher than the reference equivalent threshold sound pressure level (RETSPL) prescribed by American National Standardization Association and the age-matched thresholds recommended by a foreign literature (P<0.05 or P<0.01).The hearing thresholds in the high risk group elevated dramatically than that in the low risk group at 9,12.5,16 and 18 kHz(P<0.05 or P<0.01).As frequencies increased, the detection rate of hearing thresholds in the high risk group decreased gradually, and at 18 and 20 kHz it was significantly lower than that in the low risk group (P<0.01).Conclusion EHF audiometry is a helpful tool for early detection of noise-induced hearing loss in student pilots.Hearing health care should be emphasized in civilian student pilots.It is recommended to avoid the use of personal listening devices or reduce the use time of them.